Throttle valve operating mechanism



Oct. 13,1931.

A. W. BRUCE THROTTLE VALVE OPERATING MECHANISM Filed Jan. 16, .1928

Patented Oct. 13, 1931 ALFRED w. BRUCE, F new YORK, my.

PATENT OFFICE THROTTLE VAJLVE OPERATING MECHANISM Application filed January 16, 1928. Serial. No. 247,027.

This invention relates generally to the class or type of appliances known as throttle valveoperating mechanisms, and its object is to provide a throttle lever which is freely floating relatively to the boiler, so that. the

parts can be set whenthe boiler is cold, without regardto its subsequent expansion; and

to provide connections between said, lever I asusual, on the rear end of the boiler, is proand the valve shaft, such that theinitialan- 1o gular movement of the lever, and consequently its leverage in opening the valve,are relatively very great, diminishing asthe valve is opened; such that the throttle lever will not be seriously affected by the opening and shutting shocks of the valve, and such that,

as the throttle lever is swung to open or close the valve, its fulcrum being floating, the resultant force, usually absorbed by the fulcrum bracket, is taken on the valve shaft through an equalizer, thereby applying an additional equalizing turning moment on said shaft for a given pull on the throttle lever handle. 7

The improvement claimed is hereinafter 5; fully set forth.

In the accompanying drawings: Figure 1 1s a side elevation, on a reduced scale, of a locomotive equipped with the improved mechanism; Fig. 2, a side elevation of the throttle lever end of the mechanism;

3, an end view of the par'tsshown, 1n Flg.

2; Fig. 4,v a plan view of theparts shown in Fig. 2; Fig. 5, a side view of the throttle valve shaft end of the mechanism; and, Fig.

6, a diagram, showing the angular movement of the throttle lever and the corespondin'g rectilinear movement of the pull rod.

In the practice of the invention, referring descriptively to the specific embodiment thereof which is herein exemplified, the throttle valve operating shaft, 1, is connected, as usual, through its crank arm, 3', and pull rod, 2, to thethrottle lever mechanism in the cab, but said rodis not directly connected to the lever, 4, itself, but indirectly, as will hereinafter appear. Z The fulcrum, 6,.of the throttle lever, 4, lies latch portion, 7, of said lever, the handle 59 lying below the fulcrum, and the quadrant,

' Points 6, f, g and h represent the correspond- 8, for the latch portion, lying above the fulcrum, .as shown. I By this arrangement of the throttle lever, with its quadrant lying above the fulcrum, and its handle portion below the same, almost one foot more head room is afforded in the cab than with the usual arrangement. The lever supporting bracket, 9, mounted,

vided with guideways, 10, for a slide, 11, which'carriesthe quadrant, 8, and the fulcrum, 6, and which is provided with the extension 12, slidably engaging the guideways 10. Said slide is connected at 13, by the rod,

2, to the crank arm, 3, on the valve shaft, 1, which also carries a second crank arm, 15,

' projecting in a diametrically opposite direction from the first crank arm, 3, and being pivotally connected to a second connecting rod, 14, running parallel to, and below, the rod 2, to the cab. The rear end of rod, 14, is keyed at 16 to a cross-head, 17, slidable in guides, 18, formed in the slide, 11, and having PIVOtGdtO it at 19,'the end of a double link, 20, which is bent to pass over the ful- 7 crum, 6, and is pivoted, at its other end, 21, to the rear end of an arm, 22, rigidly secured to, or formingpa-rt of, the throttle lever, 4, at its fulcrum, 6, and extending rearwardly therefrom. By this arrangement of the connections between the throttle lever and the valve shaft, 1,very advantageous conditions of operation result, since the angular movement -;of. the lever, and, consequently, its leverage,

are relatively very great for the first inch of 86 travel of the valve shaft connecting rods, beingconsiderably reduced for the second inch oftravel, and still more reduced for the third inch of travel of said rods. This is graphically shown by the diagram of Fig. 6,-in which points a, b, 0, and d, represent the consecutive positions of the handle end of the lever required to move a point, i, .on the pull rod through three inches of travel to point, la.

ing consecutlve positions of the connecting v pivot, 21, of the lever arm, 22, and the link, intermediate the handle porti0n, 5, and the '20 rod, 14., will be pushed to the right by. the link, 20, and its connection to the arm, 22, of the lever, 4, which will swing the crank arm, 15, to the right, turning the valve shaft, 1, to the left. This swings crank arm, 3, to the left, pushing rod, 2, to the left, and, consequently, the slide, 11, with the lever fulcrum, 6, and quadrant, 8, also to the left. This movement of the throttle lever fulcrum to the left partially neutralizes the effect of the swinging of its handle to the left, and, consequently, the arc of travel of the handle about the fulcrum is relatively further increased for the first increment of rotation of the shaft, 1, to open the valve. The length of the arc diminishes for the succeeding increment-s, as illustrated in Fig. 6. Also, the shaft, 1, is turned by equalized forces applied on opposite sides of its axis, as has been already explained.

The described advantages of greater leverage at first, whereby the valve is initially opened with less force, are due, principally, to the arrangement of the bell crank arm on the lever and the link connecting said arm to the rod, ane are not dependent upon the fact that the throttle lever fulcrum is floating, but can be obtained substantially as well with a fixed fulcrum lever. The disadvantages of the latter, however, are well known, and the best results are obtained when the combination of floating fulcrum and bell crank and link connection, as described, is used.

I'Vhat is claimed as the invention and desired to be secured by Letters Patent is:

1. In a locomotive throttle valve operating mechanism, the combination with the valve shaft, of a throttle lever having a. floating fulcrum, a rod connecting said fulcrum to said shaft, and connections from said lever to said shaft on the opposite side of its axis from said rod connection.

2. In a locomotive throttle valve operating mechanism, the combination of a throttle lever having a floating fulcrum and a rearwardly projecting bell crank arm, and separate connections from said fulcrum and from said arm to the valve shaft whereby the turning moment applied thereto is equalized.

3. In a locomotive throttle valve operating mechanism, the combination of a throttle lever, a valve shaft, opposite crank arms on said shaft, a supporting bracket on the boiler, a slide in said bracket carrying the lever fulcrum, and separate rods connecting said arms with said slide, and with said lever, respectively.

4. In a locomotive throttle valve operating mechanism, a valve shaft, opposite crank arms on said shaft, a throttle lever having a floating fulcrum, a slide carrying said fulcrum, an arm on said lever projecting rearwardly from its fulcrum, a link pivoted at one end to the end of said arm, a rod connected to the other end of said link and connected to one Lea/glee of said crank arms, and a rod connecting said slide to the other of said crank arms.

5. Locomotive throttle valve operating mechanism, comprising a bracket mounted on the boiler and having guideways, a slide fitted in the latter, a quadrant carried by said slide, a throttle lever playing over said quadrant and fulcrumed on said slide, a throttle valve shaft, opposite crank arms on the shaft, a rod connecting one of said arms to said slide, a lateral arm on said lever, a link pivoted to the end of said lateral arm, and a rod connecting said link to the other crank arm on said shaft.

6. In a locomotive throttle valve operating mechanism, the combination of a valve shaft, a crank arm, a rod pivotally connected at one end to the crank arm and extending rearwardly of said shaft, 2. throttle lever fulcrum at the rear of the opposite end of said rod, a link pivoted at its forward end to said opposite end and extending rearwardly having its rear end terminating at the rear of said fulcrum, an arm pivoted to swing with said lever and extending rearwardly thereof and.

having its rear end pivotally connected to the rear end of said link.

7. In a locomotive throttle valve operating mechanism, a valve shaft rotatable to open the valve, a lever for rotating the shaft, and;

connections between the lever and shaft comprising means providing a floating fulcrum for said lever, and other means comprising a rod connected at one end with the shaft, an arm extending from the fulcrum connec. tion of the lever in substantial parallelism with the rod when the valve is in closed position, and a link connecting the rod with the end of the arm opposite the fulcrum connection, whereby an initial angular movement of the lever to open the valve will produce a relatively small initial angle of rotation of the shaft.

8. In a locomotive throttle valve operating mechanism, a valve shaft rotatable to;-

open and close the valve, shaft-rotating means secured to the shaft, a valve-adjusting control lever, a double means co-operating in adjusting the valve, each of the means constituting said double means being secured at:

one end to said shaft-rotating means and at the other end to said lever, and means for locking the valve in any adjusted position.

9. In a locomotive throttle valve operating mechanism, a valve shaft rotatable to operiand close the valve, shaft-rotating means secured to the shaft, a valve-adjusting control lever having a floating fulcrum, a double means co-operating in adjusting the valve,

each of the means constituting said double" means being secured at one end to said shaftrotating means and at the other end to said lever, and means for locking the valve in any adjusted position,

10. In a locomotive throttle valve operat ing mechanism, an operating structure comprising two substantially parallel reciprocable parts, a member pivotally connected at spaced points to adjacent ends of said parts, and a crank member pivotally connecting the two parts together at their opposite adjacent ends, a valve shaft secured to the crank member between its pivotal connections adapting the shaft to be rotated thereby, and operating means secured to said structure whereby the reciprocable parts may be moved in opposite directions.

11. In a locomotive throttle valve operating mechanism, an operating structure comprising two substantially parallel reciprocable parts, a member pivotally connected at spaced points to adjacent ends of said parts, and a crank member pivotally connecting the two parts together at their opposite adjacent ends, a valve shaft secured to the crank member between its pivotal connections adapting the shaft to be rotated thereby, and an operating lever secured to said structure whereby the reciprocable parts may be moved in opposite directions.

12. In a locomotive throttle valve operating mechanism, an operating structure comprising two substantially parallel reciprocable parts, a member pivotally connected at spaced points to adjacent ends of said parts, and a crank member pivotally connecting the two parts together at their opposite adjacent ends, a valve shaft secured to the crank member between its pivotal connections adapting the shaft to be rotated thereby, and an operating floating lever secured to said structure whereby the reciprocable 7 parts may be moved in opposite directions.

13. In a locomotive throttle valve operating mechanism, an operating structure comprising two substantially reciprocable parallel parts, a member pivotally connected at spaced points to adjacent ends of said parts, and a crank member pivotally connecting the two parts together at their opposite adjacent ends, a valve shaft secured to the crank member between its pivotal connections adapting the shaft to be rotated thereby, and an operating lever secured to said pivotally connected member at one of the said spaced points whereby the reciprocable jecting from opposite sides of said shaft, means comprising a pair of rods reciprocable in opposite directions, each having one of its ends operatively secured to one of said arms for operating the shaft, and a lever for operating said means having a floating fulcrum.

16., In a locomotive throttle valve operating mechanism, a valve shaft, a rod con- 7 nected at one end with the shaft, and means for reciprocating the rod comprls ng a p1v-v oted lever, an arm secured to pivot with the lever and adapted to extend in substantial alignment with the rod when the valve is in closed position, and a link connecting the end of the arm remote from the pivotal connection with the rod. i

17. In a locomotive throttle valve operating mechanism, the'combination of a throttle lever having a laterally projecting bell crank arm, a valve shaft having a crank arm, a link pivoted at one end to the end of said bell crank arm, a rod connecting the other end of said link to said crank arm, and connections from said lever to said shaft on the opposite side of its axis from said rod connection.

ALFRED W. Bmicn.

parts may be moved in opposite directions.

14. In a locomotive throttlevalve operating mechanism, a valve shaft, two arms projecting from opposite sides of said shaft, means comprising a pair of rods, reciprocable in opposite directions, each having one of its ends operatively secured to one of said arms for operating the shaft, a bracket for supporting said means, and a member for operating said means, said member being pivotally secured to said means to have movement bodily therewith relative to said bracket. 7

15. In a locomotive throttle valve operating mechanism, a valve shaft, two arms pro- 

